Line protective device.



J. ERIGKSON.

LINE PROTEGTIVE DEVICE. APPLICATION FILED 33.14, 1912.

Patented Oct. 13, 1914.

UNITED STATES r grnutr orrrcn 4 JOHN EBIGKSON, OF CHICAGO, ILLINOIS, ASSIGNOR T AUTOMATIC ELECTRIC COM- PANY, OF CHICAGO, ILLINOIS,

A CORPORATION or I'LLINoI's.

LINE PROTECTIVE DEVICE.

Specification of Letters l' atent.

Patented Oct. 13, 1914. 4, 1912. Serial No. 677,615.

To all whom it may concern Be it known that 1, JOHN ERICKSON, a citizen of the United States of America, and resident of Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Line Protective Devices, of which the following is a specification.

My invention relates to line protect ve de vices, and more particularly to that class pf rotective devices which employ heat C0115 or operating the same.

My invention'is in the nature of an improvement upon the line protective device shown and described in my coending application Serial Number 661,78 filed November 22, 1911.

My present invention difiers from in previous invention in that I employ a sel soldering heat coil,-and, furthermore, I rovide improved means 'for mounting his heat coil, whereby it is held firmly against rotation.

These and other objects of my invention will be more readily understood by reference to the accompanying '-drawings,'in which Figure 1 is a plan view of a pair of the protective devices mounted. upon opposlte sides of a mounting plate. Fig. 2 is a side elevation of a portion of the mountin plate showing two of the protective evices mounted upon the sameside of the plate. Fig. 3 is a sectional view of the heat coil.

The mounting plate is composed of two 86 plates 2 and 3 riveted together. Mounted upon each side of the mounting plate there area plurality of groups of flexible contact springs 4, 5, 6 and 7 and stiff heat .coil supports 9. The two sets of springs which are mounted o 'te each other preferably form a pair tothe tfwo side's of the. same line circuit. Ordin 1 carbon lightning arresters 23 are clamp between. thespring 5 and the mounting. plate, which is ordinarily Tunded'. The" sprin 1 is mounted next t e mounting or un plate and may be used to close an :1 arm circuit when pressed .into contact with said plate; The spring Bis a stationar sprin its fund tion being to-hold the car nrester in. lace and to furnish 'a' connection betweene spring 6 and the lightning arl a spring 6 is the. line springthat is, @the f which is:- commando,

board springthat is, the spring which is connected to the switchboard inside the central oilice. Electrical connection is normally maintained between the springs 6 and 7 by means of a heat coil which is mounted ,upon the support 9. This heat coil comprises a U-shaped member 10 to which there is insulatingly secured a pin 11 around which there is wound a coil of resistance wire 12. A protecting shell 15vis slipped over the winding 12. One terminal of the winding 12 is connected to the member 10 and the other terminal is connected to the pm 11. The limbs of the U-shaped member 10 areprovided with rectangular openings which may he slipped down over the end of the support 9. The end of the pin 11 is provided with a slot in which there ispivoted a lever 13. A small quantity of solder is placed in the slot in which the lever 13 is mounted tohold it rigid. Near the top of the spring 6 there is a small lug 14, immediately above which there. is an opening through the sprin i The protective evice is set in the following manner: The U-shaped member 10 of the heat coil is sli ped down over the top of the support 9 an the sprin 6 is forced optward until the lower end 0 the lever 13 may be slipped down behind the lug 1%, as shown on the right-hand side of the mounting plate is a connection from the switchboard spring 7 through the member 10, winding 12, in 11, lever 13 and the lug 14 to the line spring 6. When an abnormal currentflows over this circuit for an undue length of time, the winding 12 heats. up and softens the solder sufliciently' to allow the lever 13 to be tipped up by the-spring 6 and release it. When thesp'ring 6 is released it assumes the position shown on the left side of the mounting plate in Fig. '1 and becomes disconnected rom the switchboard spring 7. In this position 8, lug 16 on the spring 6 passes through an opening in the spring 5 and forces the spring *1 down onto the ground plate, therebygrounding the line spring and closing the alarm circuit When aheat'coil is op- I slated to release-the spring 6, the lever- 13 is.

' shifted in Fig. l WVhen the device is thus set there fromithe position shown ongthef right hand of the mounting plate-to thit,

shown at the of said plate, jandthe' soldeg upon cooling, secures the; lever-in its sprin p 55 h ide line. e spring 7 is the switchnew pomtion; In order to reset the -device 1 6 on one side of the mounting plate an all the switchboard springs 7 on the other side are crossed over to the opposite side, so as to bring all the line terminals on one, side and all the switchboard terminals on the other side. The crossed-over terminals are passed through openings in; the insulating washers 18 to stiffen them.

The switchboard spring 7 is not rigidly connected with the he'at coil support 9,;but

simply. bears against it by its own tension. The ordinary test plug may thus be inserted.

between the spring -7 I and the support 9, thereby disconnecting-.the line from the switchboard, so that the line maybe tested either in'or out as desired.

The rear portions of the mounting plates 2 and 3 are ofiset so asto make the rear portion of the mounting plate approximately of the thickness of the lightning arresters. The mounting strips are generally. long enough to carry ten or twenty pairs of the protectors. At each end of the strip one of the plates 2 or 3 is provided with a semicircular projection 19, while the other plate is prm ided with a corresponding semi-circular cavity or notch. At one end of the strip the lug is in the plate 2 and at the other end in the plate 3. 'A number of the strips may thus be placed'end to end and a lug on each strip will fit into a notch in the adjacent strip, and a bolt may be passed through the holes 20 in the two plates, thus forming a rigid connection between the two.

\Vhile I have illustrated my invention in connection with one specific structure, it is to be understood that in certain aspects my invention is of broader scope, and that I do not Wish to be limited to the exact construct'on shown and described.

What I claim as my invention is 2-- 1. In a line protective device, a supporting arm, a heat coil having a U-shaped plate connected to one end of said coil, and a pairof openlngs in said plate through whichsaid supporting arm is adapted to pass in order to secure said heat coil to said arm.

2. Infa lineprotective device, a supporting arm, a heat coil having a U-shaped plate connected to one end of said coil,,and a pair of angular openings in .said plate through which saidsupporting arm is adapted to"- ed to pass, whereby said heat coil is firmly secured to said supporting arm.

4. In a line protective device, a ground plate, spring members suitably mounted thereon, a heat coil normally engaged by one of said spring members, said heat coil having a trigger provided with a pair of catches, and a lug carried by one of said spring members and engaging one of said catches, said heat 0011 being removable,

whereby it may be turned over, said lug being adapted to engage the other catch when the heat coil is so turned.

Signed by me at Chicago, Cook county, Illinois, this 9th day of February, 1912.

JOHN ERICKSON.

lVitnesses I ARTHUR J. RAY, ALBERT ANDERsEN.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, 7 Washington, D. 0. 

